Superheater boiler



Dec. 7, 1937. T sTlLLMAN 2,101,106

'SUPERHEATEB BOILER Filed July 12, 1935 6 Sheets-Sheet l Fig INVENTOR 7 7770172675 15. SIfi/lman 6 Sheets-Sheet 2 Filed July 12, 1935 INVENTOR Thomas 5. 55/7/2770]? Dec. 7, 1937. T. 13., STILLMAN SUPERHEATER BOILER F iledJ uly 12, 1935 6 SheetsShee1; 3

O O O O O O O O O O O O O O O O O O O O O O OH? O OO O INVENTOR Thomas 5.5L! l/man SUPERHEATER BOILER Filed July 12, 1955 6 Sheets-Sheet 4 INVENTOR 777017705 5. SUI/ma]? Dec. 7, 1937. 'r. B. STILLMAN 2,

SUPERHEATER BOILER Filed July 12, 1955 6 Sheets-Sheet 5 T ,1 5? I I 0oOOOOoOoooovc0000000000000 INVENTOR 7720177455 SLzY/Inan Dec. 7, 1937.

T. B. STILLMAN SUPERHEATER BOILER Filed July 12, 1955 Y e Sheets-Sheets INVENTOR. T/zomas B. Stillmqn aim? ATTORNEY.

Patented Dec. 7, 193i UNITED STATES PATENT OFFICE SUPERHEATER BoI Ea Thomas a. Stillman, South Orange, N. a, assignmto The Babcock & Wilcox Company; Newark, N. J., a corporation of New Jersey Application July 12,

I 7 Claims.

. ment 'is one example. Separate settings for inde- Posed upon armament by the latter and aninferior operating and maneuvering efiectiveness pendently fired siiperheaters and boilers illustrate another. Excessive tonnage limitations .are imresults from the former. Itis an object of the invention to provide steam generating and superheating equipment the use of which eliminates such disadvantages. q

By providing a separately fired high temperature superheater 'co-ordinated with a high pressure water tube steam boiler in a single boiler setting with two. independently operating furnaces, the use of the invention results in a superior overall ship eflicienc'y and maneuvering capacity. .Also, effective "control of superheat temperatures. over the wide ranges of navy and other marine requirements is gained without the necessity of employing auxiliary equipment such as desuperheaters, which impose additional weight limitations.

The invention will be described by reference to the accompanying drawings in which:

Fig. 1 is a view in the nature of a vertical section through the superheater furnace and the boiler furnace of a marine boiler. I

Fig. 2 is a view in the nature of an'elevation, showing the superheater.- e

Fig. 3 is a. detailed view showing one or the superheater sections in plan.

Fig. 4 15.9. section taken on the line 4-4 of Fig. 'l. v v

Fig. '5 is a partial transverse section through the studded tube inter-furnace wall.

Fig. 6 is a partial transverse section showing a modification of the inter -furnace wall in which a partially shidded construction is employed.

Fig. 7 is a viewin the nature of a transverse section showing another modification of the marine boiler having independently fired boiler and superheater furnaces within the same boiler setting. v i

Fig. 8 is a detailed section showing themanner in which the superheater tubes are maintained in position from the large diameter tubes connected into boiler-circulation; I

Fig. 9 is a detailed vie'w'of the superheater sup- 1935, Serial No. 30,950

port, looking at the Fig. 8 construction at right angles thereto. 1 v

Fig. 10 is a floor plan view showing some of the floor tubes bare and others covered with a re-' fractory material. Fig.1! is a view in. the nature of a vertical transverse section of another steamboiler.

The steam generator and superheater indicated .in Fig. 1 of the drawings is for installation on shipbbard'where'the steam coming fromtthe fire rooms to the turbines may have a pressure of the order of 900# per square inch and a temperature 011900" F. It is inherently capable of such superheat control that it attains a close regulation of superheat over wide ranges independently of the rating at which. the boiler is being operated. This is'particularlv advantageous under ship maneu'vering conditions when suprheats from 100' F. to 370 F. are desidereitums according to the changes in ship operation. When a ship is operating at a reduced speed'and the boiler is operating at a low capacity itis important from the viewpoints of cruising range and economy to maintain a high superheat, and the illustrative superheater boiler produces this result.

Fig. l, indicatesjin a single boiler setting, a superheater furnace ill and a boiler furnace i2. vThe former is separately fired by the independently operable burners l4 and its furnace gases pass across the superheater IS on their way through .the air heater iii to the flue.20. Hot

gases from the boiler furnace I2 pass across the bank of steam generating tubes 22 and thence over the economizer 24to the flue 26.

The illustrative boiler is a three drum boiler having a single steam separator drum 28. The-- remaining drums 30 and 32 are preferably bottom supported as shown, upon pedestals 34 and 3B which are secured at positions near the sides of i the hold of a ship. v v

' The separator drum or steam and water drum 28 is supported by the downwardly, diverging groups of tubes which connect it with the-lower drums. It therefore is free to move vertically as the temperature of the fluid in the tubes increases.

Steam from the separator drum may pass through the ofitake 3B and the line 40 to the superheater header 42 if the valve 44 is open; or

it maypass as saturated steam directly to a consumer, through the valve 46 and the line 48. This arrangement of elements is particularly adaptable to ship operating conditions. In port, saturated steam only may be used, and even under some operating conditions saturated'stea'm desired. This is permitted by the present boiler.

When the superheater consists of U-tube sections such as those indicated in Figs. 2 and/3.

of the drawings it may be maintained in position by large diameter water tubes 50 communieating with the drums 28 and 32.

cates these tubes in widely spaced pairs posi- Fig. 3 inditioned between the legs of the U-tubes. Each tube has an apertured side plate 52 fixed thereto, and the U-tubes are inserted in apertures 56 during the construction of the boiler.. Figs. 8 and 9 illustrate the manner in which these plates are secured to the tubes. Ashere shown, the plates are welded to collars 58 which encircle the tubes and may be movable relative thereto to compensate for differential expansions and contractions.

Fig. 3 further indicates each superheater section as having a plurality of nested U-tubes all of which communicate with separate inlet and outlet headers at their ends. At one end of the particular section here shown, one leg of each U-tube is connected to the inlet header 42, and at the other end, the other legs are connected to the outlet header 51. The latter header of the first section may be directly connected to the inletheader of the similarly formed succeeding section and similar connections made throughout the entire superheater.

Fig. 1 shows the superheater I6 protected against overheating damage by the rows of screen tubes 58 and 68, the latter of which may have refractory coverings indicated at B2. The furnace wall tubes 66 may be similarly covered. Two forms of the covering for the latter are indicated in Figs. 5 and 6. In both, refractory material fillsthe spaces between the tubes to complete the wall. The wall 62 is preferably not a closed or complete wall, while the covered tubes 64 form a closed or complete wall.

In the Fig. 6 modification,'the tubes 64 have headed metallic studs 66 welded thereto with their heads at their tube ends. They preferably extend radially from the tubes although in some instances some of the studs may be otherwise arranged. In the Fig. 6 modification, for example,

there are studs 66 only in the spaces between successive tubes, and the refractory material 18 preferably installed as a plastic, is correspondingly positioned.

When the inter-furnace wall is constructed according to the Fig. 5 modification in a high temperature zone, the wall tubes 64 permit higher boiler capacity. Higher furnace temperatures are also promoted. In ignition zones, complete combustion is attained at an early stage in-the path of furnace travel. Heat radiantly transmitted from the incandescent refractory material contributes to this result.

The Fig. 6' modification isadapted for lower temperature Zones, or lower temperature furnace conditions, the tubes being partially bare.

The wall tubes 64 connect the floor header H with the water space of the drum 28 and are maintained in a boiler circulation circuit by a tubular connection between the drum 32 and the .header ll.

Thus, the inter-furnace wall may be as thin as shown (in.the interest of increased fur- 'nace volume and low weight) and yet be adequately protected so as to minimize'boiler outage".

aromas inclined as shown and may be covered over a part of the furnace with refractory material 14. When parts of the fioor tubes are bare (as indicated at 15 in Fig. 10), the furnace is cooler,

the remaining and covered parts acting to insure proper circulation.

When' the fioor of the boiler furnace is to. be cooled, fioor tubes I6 connect the drum 38 to .the header ll, thus tying the inter-furnace wall and its tubes 64 in operative relation. The boiler furnace floor is then constructed in a manner similar to the above described construction of the superheater furnace floor. A

The spring 18 interposed relative to the fixed base 88 and the header II has a furnace floor supporting function. It is not intended to put the tubes 64 under longitudinal compression, but rather to. prevent excessive tension stresses on thesetubes (due to their floor connection) from causing damage, especially by inertia when the boiler rises'and falls due to the. action of waves on the ship.

The modification of the invention represented by'the boiler indicated in Fig. '7 is of a design similar to that shown in Fig. 1. Here, there are greater water storage and greater steaming capacities, due to the several rows of steam generating tubesal which are positioned rearwardly of the superheater 82. The latter is supported from the single row of larger diameter tubes 84, and is generally of the same construction as the superheater in the Fig. 1 boiler. The furnace fioors, however, do not have fioor cooling tubes, but there is a circulatory connection 88 which afiords communication between the drum 90 and the floor header 92. This connection 88 has the eifect of facilitating the maintenance of uniform water temperatures-and more especially in the tube bank above the idle furnace. The tubes 94 connecting the latter directly with the water space of the drum 96 have a refractory covering 98 and are preferably bowed as shown. Furthermore, these tubes, and the wall formed thereby are protected against overheating by a metallic stud construction such as that shown in Fig. 5,

or Fig. 6, or both, the latter being used near the upper ends of the. tubes.

Fig. 4 indicates the burners I02 for the superheater furnace IUU, having fuel conducting means I'M. This figure also shows the circulatory connection 88 positioned beneath the inclined portion Hill of the furnace I00.

When the burners l4 are controlled according When the operation of the boiler furnace is automatically controlled a pressure responsive element is employed. .This may be installed in the saturated steam space. In Fig. 1 such an element is shown at H8, mounted in the T H9. It is connected by a fluid line I28 with valve operating mechanism I22 which may be similar to the valve operating mechanism for the burners of the superheater furnace. When this valve controls the fuel supply line which is common. to a plurality of the burners separate hand operated valves I24 in the individual fluid lines may be employed.

The air supply lines to the burners may be also automatically pressure or thermally controlled, by systems which are similar to those described in the preceding paragraphs.

Referring to the boiler shown in Fig. 11 of the drawings there are two furnaces I20 and I separated by wall tubes I32 and I34. The latter are connected into the circulation of the left hand boiler, and the former with the circulation of the right hand boiler. Preferably the inter-furnace wall includes the wall tubes in a they are separately connected to headers I44 and I46. Floor tubes I 48 lead from the header I46 to the lower drum I50. The latter is connected by a bank of steam generating tubes I52 to the drum I40. Steam is conducted from the latter drum through the oiftake I53 to a union I54 from which the steam may be led through the valve I56 and the line I56 to the superheater I60, or it may pass as saturated steam' through the valve I62 to a point of use.

From the floor header I44 the wall tubes I64 lead to the drum I66. This drum is connected to the drum I42 by screen tubes I66 and superheater supporting tubes I1 0. Rearwardly of the superheater I60 the steam generating tubes I12 connect to the drums I42 and I66. Steam from the drum I42 passes through the oiftake I14 to theunion I54.

The furnace I30 is fired by a number of fuel burners herein shown as the oil burners I16.

The other furnace I28, is fired by the oil burn- I ers I18.

What is claimed is: v

1. A separately flred superheater and a steam generator combined in a unitary steam power installation from which wholly saturated steam or wholly superheated steam may be optionally supplied, means forming a steam and water chamber which acts as a separator, means forming two independently operable furnaces with separate gas outlets on opposite sides of the separator, means forming submerged water chambers below the separator and on opposite sides thereof, inclined steam generating tubes arranged in opposite banks each of which directly connects one of said water chambers to the separator, the tubes of each bank being respectively wholly disposed over one of said furnaces, upright tubes disposed between said furnaces and connected to said separator, means connecting said upright tubes into the boiler circulation, refractory means supported by the upright tubes and closing the inter-tube spaces to complete a fluid cooled wall separating the furnaces, a superheater disposed wholly over one of said furnaces, and means for optionally discharging steam from said separator through said superheater or direct to use.

2. In combination, means forming a steam and water chamber acting as a separator,- means forming two submerged water chambers, in-

'clined banks of tubes directly connecting the of said banks, a superheater furnace wholly beneath said bank; a boiler furnace wholly be- 1,

neath the other bank, a row of upright wall tubes separating said furnaces and directly connected to the separator, refractory material closing the spaces between said wall tubes to complete the wall between said furnaces, metallic studs welded rator through said superheater or directly to use,

and means forming separate gas outlets for said furnaces on opposite sides of the separator, all of said means and elements presenting a separately firedsuperheater and a steam generator combined in a unitary steam power installation from which wholly saturated steam or wholly superheated steam may be optionally supplied. 3. In a marine boiler, a unitary circulatory system including three drums communicating with upwardly converging banks of steam generating tubes, one of said drums acting as a separator directly connected .by said banks of tubes to the other drums which form submerged water chambers, a convection superheater associated with one of said banks'of tubes, a superheater furnace wholly beneath one of said banks of tubes, a boiler furnace wholly disposed beneath the other of said banks of tubes, independently operable firing means for said furnaces, means forming separate gas outlets for said furnaces above said banks of tubes and on opposite sides of the separator, said furnaces including upright .wall' cooling tubes positioned between said furnaces and connected to said separator, metallic studs welded to said last named-tubes and extending into the spaces between said tubes, ceramic refractory material so as to develop high degrees of superheat over a wide range, and means for optionally discharging steam from said separator through .said superheater or directly to use; all of the above mentioned elements and means presenting a separately fired superheater and a steam generator combined in a unitary steam power installation from which wholly saturated steam or wholly superheated steam, or both, may be optionally or simultaneously supplied.

4. In combination, a steam and water drum acting as a separator, a plurality of submerged lower water drums, oppositely inclined banks of.

steam generating tubes directly connecting the system being I lower drums to the steam drum and supporting the latter, a superheater associated with one of said banks, a superheater furnace beneath the last mentioned bank; a boiler furnace beneath the other bank, said furnaces-including a row of spaced wall tubes separating said furnaces and directly connected to the separator, metallic studs Welded to said wall tubes, ceramic refractory "material closing the spaces between said wall tubes to complete the wall between said furnaces, a wall tube header substantially below the levels of said water drums and communicatingwith the wall tubes, floor cooling tubes communicating with the wall tube header and the lowerdrums and inclined downwardly away from the lower drums to increase the volume of said furnaces, independently operable fuel burning means associated with said furnace so that saturated steam only may be generated without danger of damaging the superheater by contact of hot gases therewith and whereby different degrees of superheat may be developed according to the operation of the burning means for the superheater furnace, means forming separate gas outlets for said furnaces on opposite sides of the separator, means for optionally discharging steam from said separator through said superheater or directly to use; all of the above mentioned means and elements constituting a separately fired superheater and steani generator combined in a unitary steam power installation from which wholly saturated steam or wholly superheated steam, or both, may be optionallysupplied:

-5. In a unitary'steam power installation including a combined separately fired superheater and steam generator from which wholly saturated steam or wholly superheated steam may be optionally supplied, a water tube boiler including a plurality of banks of steam generating tubes connected to a common steam and water separator, means forming submerged water chambers on opposite sides of the separator and connected with said banks of tubes, a furnace divided into a plurality of sub-furnaces by a wall positioned below the separator and including water tubes, meansforming separate gas outlets'for the respective sub furnaces on opposite sides of the separator, a separately fired superheater associated with and wholly disposed over the first sub-furnace, separate fuel burning means for the sub-furnaces, means associated with the second sub-furnace for controlling the supply of fuel and air to its fuel burning means with reference to steam capacity and independently of superheat, means associated with the first subfurnace controlling the supply of fuel and air to its fuel burning means with reference to super heat and independently of steam capacity, whereby said second sub-furnace may be operated when the first is not in operation to cause the boiler to supply saturated steam only, the tubes of each of said banks of tubes directly connecting the separator and one of the submerged chambers with the tubes of each bank being respectively wholly disposed over one of said sub-furnaces, refractory means supported by the water tubes of said wall, and means for optionally discharging steam from said separator through said superheater or direct to use.

6. A separately fired superheater and a steam generator combined in a unitary power installation from which wholly saturated steam or wholly superheated steam may be optionally supplied, means forming a steam and water chamber which acts as a separator, means forming two independently operable sub-furnaces with separate gas outlets on opposite sides of the separator, means forming submerged water chambers below the separator and on opposite sides thereof, inclined steam generating tubes arranged in op posite banks each .of which directly connects one of said water chambers to the separator, the tubes of each bank being respectively wholly disposed over one of said furnaces, upright tubes disposed between said sub-furnaces and connected to said separator, means connecting said upright tubes into the boiler circulation, refractory means supported by the upright tubes and closing the inter-tube spaces to complete a fluid cooled wall separating the sub-furnaces, a superheater disposed wholly over one of said sub-furnaces, means associated with said last mentioned sub-furnace for controlling the supply of fuel and air to its fuel burning means with reference to superheat and independently of steam capacity, means associated with the other sub-furnace for controlling the supply of fuel and air to its fuel burning means with reference to steam capacity and independently of superheat, and means for optionally discharging steam from said separator through said superheater or direct to use.

'7. In a power steam unit including a separately fired superheater and a steam generator combined urated steam or wholly superheated steam may be optionally supplied, means forming a steam and water chamber which acts as a separator, means forming submerged water chambers, means forming two independently firedfurnaces with separate gas outlets, the latter means including' separate sets of steam generating tubes completing fluid communication between the submerged water chambers and the separator, some of said tubes defining a division wall separating the furnaces,-refractory means supported by the division wall tubes and arranged to close the inter-tube spaces to complete -a fluid cooled wallseparating the furnaces, the superheater being subject to contact with the furnace gases from only one of the separately fired furnaces, and means for optionally discharging saturated steam only or superheated steam from the unit.

THOMAS B. STILLMAN.

- in a unitary installation from which wholly sat- 

